Foundations of animal behaviour. Niaux caves, France. Roz Dakin. roslyndakin.com/biol321. Lecture notes posted here

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1 Foundations of animal behaviour Niaux caves, France Roz Dakin Montgomerie Lab Room 4325 Biosciences (moving to 3520) 10-15,000 years ago people travelled 5 km deep into tunnels... We ve always observed animals The course website roslyndakin.com/biol321 Lecture notes posted here To download them before class, answer the latest poll on the course blog

2 The course website roslyndakin.com/biol321 policies, schedule, syllabus lab/assignment info course blog Breakdown 8% lab attendance and participation 7% online discussion comments 12.5% project % project 2 50% labs + assignments updates discussions 15% midterm 1 15% midterm 2 20% final test 50% tests BIOL_321F on Moodle we ll use this site to hand in project reports (these must be in pdf format) we ll also use Moodle for posting grades Foundations of animal behaviour History of the field What are we studying, anyway? How do we study it?

3 Some things we got right... First written records of mutualism and brood parasitism...but he believed some goats that live near the sea never drink Ethology comes of age in the 30s Ethology: the study of the behaviour of animals in their natural habitats (from Greek) Ethos = character or habit Logia = the study of Aristotle BC Ethology comes of age in the 30s Founding fathers: Karl von Frisch, Konrad Lorenz & Niko Tinbergen Karl von Frisch Honeybee social organization & communication Worked on the waggle dance from 1920s-40s

4 Konrad Lorenz Pioneering studies of genetically programmed behaviours (instincts) in birds Studied imprinting in greylag geese in the 1930s Concept of a critical period Niko Tinbergen Puzzled and fascinated by the navigational abilities of digger wasps (c. 1929) How does a beewolf find its nest? Tinbergen solved this using the scientific method, some paint and a few pine cones Tinbergen s big contribution How do we study behaviour? We can ask 4 questions: What factors (internal and external) lead to a particular behaviour at that time? Causation How does the behaviour of an animal change as it matures? Development How does the behaviour help improve survival and reproduction? Function How has the behaviour changed over evolutionary time? Evolution

5 Tinbergen s big contribution How do we study behaviour? We can ask 4 questions: What factors (internal and external) lead to a particular behaviour at that time? Causation How does the behaviour of an animal change as it matures? Development How does the behaviour help improve survival and reproduction? Function How has the behaviour changed over evolutionary time? Evolution Two categories of causation 1. How is this behaviour caused? 2. How does the behaviour develop? Proximate causes 3. Why do animals exhibit this behaviour? 4. Why did this behaviour evolve? Ultimate causes Roaches and frogs Sensory tails (cerci) react to air movement How do cockroaches evade predators?

6 Roaches adjust their reactions Does a very young cockroach show escape response? Yes! How does the nervous system develop to ensure proper timing and direction of flight? It can adjust: if an adult looses one cercus, it can relearn escape. Reaction helps prevent capture The escape response has a built in delay: 44 ms A toad commits to direction within the first 44 ms seconds of attack Cerci are present in related insects No fossil record Comparison with other species in same family: Orthopteroid insects All have cercus-like structures All have similar nervous structures This particular response evolved soon after first insect Why do gulls tidy up? Blackheaded gulls remove egg shells from their nests after the offspring hatch

7 Tinbergen proposed hypotheses White egg shells = more vulnerable Shells might damage young Shells might make brooding difficult Shells might harbour disease Shells might attract predators Percentage Eggs not taken Eggs taken 0 White eggs Natural eggs Treatment Shells indicate presence of nests Why do blackheaded gulls tidy up? 100 Eggs not taken Eggs taken White eggs are preyed upon more Egg shells indicate nest presence to predators Percentage cm 100 cm 200 cm Distance from nest Note that Tinbergen s predictions were based on specific hypotheses: If white colour attracts predators, white eggs should be preyed upon more than mottled (natural) eggs If removal of egg shells protects chicks, the further away the shells are from the nest, the better (due to reduced predation)

8 How do we answer these questions? Three approaches to studying behaviour We ll consider 3 foundations Natural selection: differential survival due to variable, heritable traits Learning: changes in behaviour during an animal s lifetime due to experience Cultural transmission: copying behaviour from other individuals Summary We can ask questions about proximate and ultimate causes of behaviour We approach these questions using empirical, theoretical and conceptual methods Interpretations are based on natural selection, learning and cultural transmission Next time: Darwin s contributions...

9 This week in Animal Behaviour Lecture 1: Intro Lecture 2: Foundations of animal behaviour Lecture 3: Evolution and natural selection NO LABS Get textbook, read Chapters 1 & 2 Explore the course website Watch animals!